Improved version of the topology figure


Well, I think it’s improved anyway

NoC Topologies

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This took me all day, so you had better like it


Network topologiesSeriously, though, are you confused by the fact I have done the computing nodes in two different colours? Should they all be the one colour (the router nodes in the tree example should be a different colour anyway)?

Universal Credit “death march” goes on


In software development a project that is driven on, even though those working on it fear it will never work, is known as a “death march” and right now that is what the UK’s “Universal Credit” project is looking like.

English: This poster provides a good visual of...
English: This poster provides a good visual of the standard Agile Software Development methodology. (Photo credit: Wikipedia)

Claimed to be the world’s biggest “agile” software development project it has now been admitted that more conservative “waterfall” methods are being used to manage the back end of the system. That is actually a good thing in my book – because the backend manages the payment of essential benefits to millions of the poorest and most vulnerable people. Agile is not what the way to do this – you cannot tell the customer “sorry you didn’t get paid this month, we’ll tweek the system and fix the problem”.

The front end, the bit that manages people’s claims, is still being delivered in an “agile” way and that might make sense: this is about interaction between users and the system, but even here the risks are enormous and where is the testing? Testing is supposed to be what agile is all about yet all we are promised is a few small short pilots, beginning tomorrow – in other words small-scale testing with a live system. You wouldn’t do that with air traffic control or nuclear power safety so why do it with Universal Credit: and UC ought to be seen as every bit as mission critical for the UK government as those two systems.

The project is on it’s third leader in a year and more and more bits of it are being thrown overboard in a desperate effort to meet the deadlines set for political reasons.

News for the Mail on Sunday: your fridge already switches itself off “without consent”


The Mail on Sunday – I am not linking to their article – claims “sinister” technology is to be fitted in fridges which will mean they

will automatically be switched off without the owner’s consent under a ‘Big Brother’ regime to reduce the strain on power stations.

Perhaps I should not be surprised at this latest piece of mouth foaming garbage – after all this is from the stable that has done its level best to bring Britain to the edge of a public health emergency with its disgraceful campaign against the MMR vaccine, but this is really a new low.

The article contains the usual whines from manufacturers – who presumably would still be filling their fridges with the worst sort of CFCs if no one stopped them – and the hard right tin foil hat brigade:

Nick Pickles, director of civil liberties group Big Brother Watch, said: ‘This sinister plan smacks of over- the-top intrusion into people’s houses. It should be the choice of consumers  if they want to sign up to it, not slipped into our homes through fridges  and freezers.’

Anyone who has a fridge knows that its compressor engine turns on and off without direct user intervention, so why would it be so much more terrible if new fridges were fitted with devices that switch fridges off for a short period, a few seconds, when demand hugely outstrips supply?

The idea here is that consumer devices such as fridges should be fitted with probes that measure the frequency of the electricity supplied by the National Grid. If that drops too low then it is a sign that demand for electricity has significantly outstripped supply – which if it goes too far can cause far more serious effects than switching your fridge off for a few seconds.

So, as a way of regulating demand, keeping electricity prices down and carbon emissions low (as marginal generating capacity is likely to be expensive and dirty) this all makes perfect sense. But since when has sense mattered to the Mail on Sunday?

(You can read more here about the relationship between frequency and the grid. The site has a great little flash gizomo than shows the current state of play.)

Life and polyominoes


Update: It seems I got all this wrong (again!). See Hugh’s comment here

A little while ago I wrote of how I had challenged the children I work with in a Code Club to find the glider pattern in Conway’s Game of Life.

I suggested that, if they adopted an essentially random approach to putting down counters within one cell of existing counters they would need about three weeks of continuous work to find the solution as there are about 30,000 such patterns and I estimated it would take a minute, on average, to check the solution for longevity. (In fact I over estimated the average time by 50%, because, of course we should expect to trip over the correct solution, on average, at the half way point – if we adopted a truly random approach to this of course.)

Hugh who is a regular and learned commentator here then drew my attention to sequence A094169 in the “Online Encyclopedia of Integer Sequences” to suggest that there were only, in fact 3,230 possible solutions to be checked – as that is the number of five cell polyominoes (to be fair to Hugh he suggested that polyominoes were not the only potential solutions of interest).

Glider patternIn fact if we looked at polyominoes we would never find the solution – as the glider is not a polyomino – none of the five configurations has every counter/cell joined edge to edge.

But I am again forced to reduce the time – because there are essentially five glider patterns (or if you like any one glider pattern is isomorphic to four others) – and any one of them would do – so we are left with an expectation that we’d find the pattern in about 3,000 random tests – more or less the same number as the count for the pentominoes.

Schrödinger’s cat: for real


Quantum Mechanics is, along with General Relativity, the foundation stone of modern physics and few explanations of its importance are more famous than the “Schrödinger’s cat” thought experiment.

This seeks to explain the way “uncertainty” operates at the heart of the theory. Imagine a cat in a box with a poison gas capsule. The capsule is set off if a radioactive decay takes place. But radioactivity is governed by quantum mechanics – we can posit statistical theories about how likely the radioactive decay is to take place but we cannot be certain – unless we observe. Therefore the best way we can state of the physical state of the cat – so long as it remains unobserved – is to say it is both alive and dead.

Now physicists still argue about what happens next – the act of observing the cat. In the classical, or Copenhagen, view of quantum mechanics the “wave equation collapses” and observing forces the cat into a dead or alive state. In increasingly influential “many worlds” interpretations anything that can happen does and an infinite number of yous sees an infinite number of dead or alive cats. But that particular mind bender is not what we are about here. (NB we should also note that in the real world the cat is “observed” almost instantaneously by the molecules in the box – this is a mind experiment not a real one, except… well read on for that).

The idea of the cat being alive and dead at once is what is known as “quantum superposition” – in other words both states exist at once, with the prevalence of one state over another being determined by statistics and nothing else.

Quantum superposition is very real and detectible. You may have heard of the famous interferometer experiments where a single particle is sent through some sort of diffraction grating and yet the pattern detected is one of interference – as though the particle interfered with itself – in fact this indicates that superposed states exist.

In fact the quantum theories suggest that superposition should apply not just to single particles but to everything and every collection of things in the universe. In other words cats could and should be alive and dead at the same time. If we can find a sufficiently large object where superimposition does not work then we would actually have to rethink the quantum theories and equations which have stood us in such good stead (for instance making the computer you are reading this on possible).

And Stefan Nimmrichter of the Vienna Centre for Quantum Science Technology and Klaus Hornberger of the University of Duisberg-Essen have proposed we use this measurement – how far up the scale of superposition we have got as a way of determining just how successful quantum mechanics’s laws are (you can read their paper here). Hornberger and Nimmrichter's scale

They propose a logarithmic scale (see graph) based on the size of the object showing superposition – so the advance from the early 60s score of about 5 to today’s of about 12 might mean we can be one million times more confident in quantum theory’s universal application. (A SQUID is a very sensitive magnetometer which relies on superconductivity.)

And they say that having a 4kg ‘house cat’ be superposed in two states 10cm apart (which might be taken for a good example of lying dead versus prowling around) would require a score of about 57 – in other words about 10^{45} more experimental power than currently available.

That probably means no one reading this is ever likely to see a successful demonstration that Schrödinger’s cat is rather more than a thought experiment, but it does give us a target to aim at!

Dear MI5, why don’t you use my hex editor?


MI5 text fragmentThis is a semi-serious point!

Well, British security service MI5 helped to successfully convict three would-be terrorists Richard Dart (30) of Ealing, Imran Mahmood (22) of Northolt and Jahangir Alom (26) of Stratford by what looks like scanning through temporarily (?) cached fragments of Word documents. This is a good thing.

But they have been using an 8-bit orientated hex editor – as the picture shows. If they had used my Unicode supporting  editor, Hexxed, they could have got rid of those annoying spaces between the letters.

What are we going to do about stupid men?


Liz Truss, the minister for children in the UK government has today, in the sort of we’re-all-going-to-hell-in-a-handcart interview that the Daily Mail love, declared that our two year olds are ill-mannered and out of control and That Something Must Be Done. (I’m not linking to the Mail, so you’ll have to look it up if you really need to read it.)

I am not aware of any evidence to back Truss’s claims up, so here’s a far more dangerous social plague: stupid men. Stupid men who think they know everything.

The evidence for this is everywhere – look at almost any opinion poll and you’ll see that women, quite sensibly, say they “don’t know” when asked their views about some political issue. But men rarely do.

The apotheosis of this plague of stupidity dressed up as omniscience came last week when YouGov asked if “The Public Affairs Act of 1975” should be repealed. A quarter of men offered their opinion on this, while only 12% of women did. There is no Public Affairs Act of 1975 so there is no basis whatsoever on which anyone could offer an opinion.

So what is Liz Truss going to do about this?

Getting away with it


One thing that working towards a PhD has taught me is that textbooks are of low value in academia.

Of course great textbooks are essential works, but in the end a textbook is not a peer reviewed publication: it’s what you and the publisher think you can get away with.

And, yes, some text books are, in effect, peer reviewed, as they are based on refereed research (so I can now plug my friend Dr Joanne Murphy’s new book – Policing for Peace in Northern Ireland: Change, Conflict and Community Confidence – as I know it is just such a work.)

But the point about lack of peer review was brought home to me this afternoon when, fruitlessly wandering round the York University library looking for a desk, I stumbled on the politics shelves and scanned through Dominic Wring’s The Politics of Marketing the Labour Party: A Century of Stratified Electioneering.

Plaque recording the location of the formation...
Plaque recording the location of the formation of the British Labour Party in 1900. (Photo credit: Wikipedia)

Now this happens to be about something I know quite a lot about and when it comes to the 1997 election campaign I certainly think I know rather more about it than Dominic Wring – whose book maybe ought to be subtitled “Labour must lose”. Words and phrases such as “authoritarianism” and “hollow populism” and “empty rhetoric” are sprinkled through the pages and no justification offered for such judgements – and this is what suggests to me it lacks any sort of peer review, for clearly a reviewer would demand something more than the author’s political prejudices as a basis on which to make such claims?

Wring is, of course, a member of the Labour Party.

Well, my point is not to tackle Wring’s hatred of New Labour (though it’s a bit much for him to describe the 1996 Littleborough and Saddleworth byelection as turning point as though it marked the start of the decline of Tony Blair – as he subsequently went on to win three general elections), but to highlight the unreliable nature of textbooks. So I’ll stop it there.

Pseudo-science take down


This is not usually the sort of stuff I blog on, but this demolition job on the pseudo-science promoted by Jonas Himmelstrand, a Swedish “expert” who turns out to have no qualification of any worth in the subject he pontificates on (the mental health of children), in the Observer is so masterly that it deserves more coverage.

Here’s a key passage:

Himmelstrand’s talk received enthusiastic coverage in the Daily Mail andDaily Telegraph, which referred to him respectively as a “researcher” and “psychologist”. Lynne Burnham, the secretary of Mothers at Home Matter, told the Observer that Himmelstrand’s research was “all based on proper scientific figures”. She said: “He works quite closely with an American professor and sociologist. I can certainly send you some of his research papers.”

When contacted by the Observer, however, Himmelstrand said that he had been “self-taught”, although his late father was an internationally known sociologist. “I cannot say I have an academic degree, and I have never claimed to have one,” he said. “Some British media have mistakenly written that I am a sociologist. This is not correct.” In the introduction to his House of Commons talk, he said that he was the founder of the Mireja Institute and a “faculty member” of the Neufeld Institute, founded by Canadian psychologist Dr Gordon Neufeld. Last week, however, he conceded that Mireja was a “one-man outfit”. The Neufeld Institute says on its website that it invites people to become “faculty members” if they complete an advanced course in home-schooling and a two-year internship at its “virtual campus”, at a cost of more than £8,000.